Tire-alarm.



Patented May 6, 1913 J. B. POLO.

TIRE ALARM.

APPLICATION FILED Amm. 1912.

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JOSEPH B. POLO, 0F CLEAR LAKE, SOUTH DAKOTA.

TIRE-ALARM.

Specification of Letters Patent.

Application led April 27, 1912.

Patented May 6, 1913. Serial No. 698,512.

To all whom it may concern:

Be it known that I, JOSEPH citizen of the United States, residing at Clear Lake, in the county ofDeuel and State of South Dakota, have invented certain new and useful Improvements in Tire- Alarms,of which the following is a specification, reference being had to the accompanying drawings.

This invention comprehendscertain new and useful improvements in automobile appliances or accessories, and relates particularly to the class of attachments known as tire alarms. l

Theinvention has for its primary object a simple and eiiicient device of this character which may be easily applied to the valve stem of a pneumatic tire and which will automatically produce an audible signal B. PoLo, a

when the air pressure becomes reduced belowI a predetermined point or increased above a predetermined limit of inflation, the device remaining' inoperative so far as its signal producing apparatus is concerned, While the pressure remains between the predetermined maximum and minimum points between which it is desired to have the tire inflated and'interfering in no wise with the serviceability or resiliency of the tire.

A further object of the invention is a simple, durable and eflicient construction of tire alarm, the parts of which may be easily manufactured and assembled and which will not be liable -to get out of order, and which will be so arranged that they may be `adjusted, so that the points of minimum and according to the particular tire to which the device is attached. And the invention also aims to generally improve devices of -this class and to render them more useful and commercially desirable.

With these and other objects in view as will more fully appear as the description proceeds, they invention consists in certain eonstructions, arrangements and combinations of the parts 'that I shall hereinafter fully describe and claim..

For aA full understanding of the invention, reference is to be had to the following description and accompanying drawing, in

which, 4

Figure 1 is a side elevation of a tire alarm embodying the principles and improvements of my present invention. Flg. 2 1s a longitudinal sectional view thereof on the line 2-2 of Fig. 5. Fig. 3 is a similar View on the line 3-3 of Fig. 5, and, Figs. 4 and 5 are transverse or horizontal sectional views on the lines 4-4 and 5-5 ofFigs. 2 and 3 respectively.

Corresponding and like parts are referred to in the following description and indicated in all the views of the accompanying drawing by like reference characters.

My improved tire alarm includes a casing l, which is formed in the present embodiment of the invention with three longitudinally extending bores designated 2, 3 and 4 respectively, said bores being arranged in equidistant relation to each other as clearly illustrated in Figs. 4 and 5. The casing l is interiorly threaded at one end as indicated at 5 for engagement by a threaded bushing (3, said bushing being interiorly threaded as indicated at 7 whereby it maybe readily attached to the ordinary screw threaded nipple 8 of an iniiation valve stem 9 of the ordinary pneumatic tire.

One end of the bore 2 is interiorly threaded as indicated at 10 to receive the plug 11 which is secured therein and which is formed with a longitudinally disposed opening 12 extending therethrough and. terminating at its outer end in a valve seat 13. A valve 14 is adapted to engage the seat 13, the said valve being pressed inwardly on its seat by means of a coiled expansion spring 15 which encircles the valve stem 16 and which is secured at one end to a collar 17 formed on the valve .stem and at its other lend to a collar 18 formed onI the inner end of atension adjusting screw 19 which works in the outer end of the bore 2. Preferably the "screw 19 is provided with a jam nut 20 whereby it may b e securely held in adjusted position. The bore 3 1s also interiorly threaded at its inner end as indicated at 21 for the reception of a threaded plug 22, said plug being formed with an opening extending therethrough and communicating at its ends with an inwardly facin valve seat 23 and an outwardl facing va ve seat 24. A double headed valve 25 has the shank which connects its two heads together mounted in the opening formed in the bushing 22, the

two heads' ofthe valve being adapted to alternately engage the valve seats 23 and 24 respectively, as. will be hereinafter more fully set forth. The 'Valve 25 is rovided with a' stom 26 which is mounte in the bore 3 and which is encircled by a coil spring l 27, one end of said spring being screwed to the valve stem and the being screwed to a collar formed on other end of the spring a collar which is formed on the inner end,

of a thumb screw -28 which works in the outer end of the bore 3 and is preferably milled or serrated on its -periphery so that it may be easily manipulated.

The bushing 6 hereinbefore mentioned is formed with an opening 29 which leads to the inner ends of the bores 2 and 3 and which also communicates with the openingv leading into the nipple 8 in which the ordinary spring seated tire valve 30 is mounted. The relatively stationary pin 31 is, secured to the inner end of the casing 1, and it is designed, when the casing is screwed on the nipple 8 through the instrumentality of the bushing 6, that the pin 31 will engage the outwardly extending stem of the valve- 30 and move and hold the valve 30 away from itsse'at, against the tension of its spring.

The bore 4 is in open communication with the bores 2 and 3 by means oftransverse passages32 as best illustrated in Figs. 2 and V5the 'bore 4 being formed with opening" 33 leading to the atmosphere." In order to produce al sound when the yair is permitted to flow into either of the bores 2'or 3, a screw threaded plugf34 is screwed into the outer end of the bore 4, said plug being formed with an annularl groove 35 in registry with the passages 32 and with a cutaway portion 36, whereby a hissing sound will be produced by the air passing around the neck formed by the groove 35 and out into and through the bore 4 past the cutaway portion 36 of the plug.

In the practical use of my improved tire alarm, the casing: 1 is screwed on the nipple 8 of the inflation valve, the pin 31 pressing the valve 30 back or away from itsv seat and thereby admitting air into the inner end of the'attachment, The spring 15 is adjusted for the high pressure. That is to say, if it be desired that the pressure in the tire shall not exceed pounds per square inch without apprising the driver or oper-A ator of the vehicle, the screw 19 is turned so as to produce a tension of 70 pounds on the spring 15 which holds the valve 14 on its seat 13. Should, then, the pressure rise or exceed 70 pounds from. any cause, itis obvious that the valve'14 will be forced outwardly, away from its seat and thus constitute a safety valve for the tire, the air which passesA around the valve 14 issuing through the bore 2 andl out into the bore 4 and to the atmosphere so as to produce an au signal. Manifestly, when the pressure is reduced by this means to the 'predetermined point,r the 'valve 14 wise interfere with the tire at its maximum ypredetermined pressecured in place,

`be covered by a detachable diblel will shut olf and in no`- operation of they mensen In the practical use of the device as an attachment designed to produce an4 audiblel signal when the tire becomes deflated from any cause `to a dangerous or undesirable point, it is to be understood that when the device is applied to the nipplef8, the thumb screw 28 is worked outwardly in the bore 3 and, owing to the connection between the thumb screw 28, spring 27 and the' collar of thevalve stem 26, the double headed valve will. be moved outwardly so that the inwardly facing valve head will be maintained on the inwardly facing valve seat 23 and thus prevent the escape of air through the opening in the bushing 22 while the attachment is being secured in place and the pin 31 isA moving the ordinary valve 30 to the open position. After the device has been the thumb screw 28 is given one or two turns in the reverse direction so as to bring it back to the normal position where, under atmospheric pressure, the two valve heads would be equally spacedfrom the valve seats 23 and 24, but, as is evident, the pressure within the tire, coming against the spring 27 will securely hold the inwardly facing head of the valve 25 on the seat 23 and thus prevent any escape of air into the bore 3 so long as the air pressure is above the predetermined minimum point. As soon as the air pressure becomes reduced' below such predetermined point, (which is governed by the tension which is imposed upon the spring 27 the said air pressure within the tire can no longer overcome the tension of the spring 27, and consequently the spring 27 will be permitted to act under such conditions to move the valve 25 inf "wai-dly a distance sufficient to hold both of from their respective the valve heads away the air may rush seats, and consequently out into the bore 3 and force itself through the passage 32, underfthe groove 35 and cutaway portion 6 of the plug 34 and out into the bore 4, escaping into the atmosphere through the opening 33 so 'as to produce an audible signal.

It will thus be understood that my improved tire alarm not only operatesA to automatically give an audible signal when theI pressure in the tire exceeds' the predetermined maximum point,s but also gives an alarm when the pressure is reduced beyond the desired minimum point.

` If desired, the outer end of the casing may cap 37; to protect the screws 19 and 28, said ca being formed with an angular slot- 38 esigned for engagement with a stud or pin 39 projecting outwardly from the ca'singl.

It is, of course, understood "-`thatfafter the inwardly facing head of the valve 25 is moved away from its seat and the air permitted to escape, a further reduction of pressure will shortly thereafter permit the spring 27 to act to move the outwardly facing head of said valve against the outwardly facing seat 24 so as to prevent the air pressure from becoming entirely exhausted.

Having thus described my invention what I claim is:

1. A tire alarm, including a easing designed for attachment to the inflation valve stem of a pneumatic tire and formed with separate bores adapted to communicate at one end with the interior of said inflation valve stem, one of said bores containing an outwardly facing valve seat, a valve adapted to rest thereon, means4 for yieldingly holding said valve on its seat, the other bore containing both inwardly and outwardly facing valve seats in communication with each other, a valve provided with two heads adapted toy alternately seat against the said respective inwardly and outwardly facing valve seats of the second named bore, and yielding means connected to the la"y named valve and tending to hold the valve in an inner position with the outermost head rest-- ing against its outwardly facing valve seat.

2. A tire alarm, including a casing designed for attachment to the inflation valve stem of a pneumatic tire'and formed with separate bores adapted to communicate at one end with the interior of said inflation valve stem, one of said bores containing an outwardly facing valve seat, a valve ada ted to rest thereon, means for yieldingly ho ding said valve on its seat, the other bore containing both inwardly and outwardly facing valve seats in communication with each other, a valve provided with two heads adapted to alternately rest against the s aid respective inwardly and outwardlyfacmg valve seats of the second named bore, and means tending to hold the valve in an in ner position with the outermost head restin against its outwardly facing valve seat, sai

meansbeing yieldable in both directions, for the purpose specified.

3. A tire alarm, including a casing designed for attachment to the inflation valve stem of a pneumatic tire and formed with separate bores adapted to communicate at one end with the interior of said inflation valve stem, one of said bores containing an outwardly facing valve seat, a valve adapted to rest thereon, means for yieldingly holding said valve on its seat, the other bore containing both,inwardly and outwardly facing valve seats in communication with each other, a valve provided with two heads adapted to alternately seat against the said respective inwardly and outwardly f acing valve seats of the second named bore a spring connected to said last named valve and tending tohold the same in an inner position with the outermost head resting against the outwardly facing valve seat, and adjusting means secured to the casing-and connected to said spring and movable in a direction to draw one head against the inwardly facing valve seat or press the other head against the outwardly facing valve seat.

ll. A tire alarm, including a casing designed for attachment to the inflation valve stem of a pneumatic tire and formed with separate bores adapted to communicate at one end with the interior of said inflation valve stem, one of said bores containing an outwardly facing valve seat,l a valve adapted to rest thereon, a spring connected to said valve and adapted to hold it on its scat, an adjusting screw working in the end of said bore and connected to said spring to adjust the tension thereof, the other bore containing both inwardly and outwardly facing valve seats in communication with each other, a valve provided with two heads adapted to alternately seat against said respective inwardly and outwardly facing valve seats of the second named bore, a spring connected to said last named valve, and an adjusting screw working in the end of the second named bore and connected to said spring and movable in a direction to 'draw one head against the inwardly facing valve seat or press the other head against the outwardly facing valve seat.

5. A tire alarm including a casing designed for attachment to the inflation valve stem ofl a pneumatic tire and formed with three separate and distinct bores extending longitudinally of the casing, one of said bores containing an outwardly facing valve seat and another containing an inwardly facing valve seat and an outwardly facing valve seat, a valve adapted to rest on the first named outwardly facing valve seat, means for yieldingly holding said valve thereon, a two-headed valve adapted to rest on the inwardly facing valve seat and. the corresponding inwardly4 facing seat, and means tending to' hold the last named valve in an inner position with the outermost head resting against the second named outwardly facing valve seat, the casing being formed with an opening leading from the third bore to the atmosphere and with passages establishing communication between the third bore and the other two bores'.

6. A tire alarm, including a casing designed for attachment to the inflation valve stem of a pneumatic tire, and formed with separate bores adapted to con municate at one end with the interior of said inflation valve stem, one of said bores containing an outwardly facing valve seat, a valve adapted to rest thereon, means for yieldingly holding said valve on' its seat, the other bore containing both inwardly and outwardly facing valve seats in communication with each other, a valve provided with two heads adapted to alternately seat against the said vso respective inwardly and outwardly facing valve seats of the second named bore, a spring connected to said last named valve and adjustable means secured to the casing and connected to said spring and movable in a direction to draw one head against the inwardly facing valve seat or press the other head against the outwardly facing valve seat.

7. A tire alarm, including a casing, designed for attachment lto the inflation valve stem of a pneumatic tire and formed with three separate and distinct bores extending longitudinally of the casing, one of said bores containing an outwardly facing valve seat andanother containing an inwardly facing valve seat, a valve adapted to rest on the outwardly facing valve seat, ingly holding said valve thereon, a valve adapted to rest on the inwardly facing valve means for yield-- seat, means tending to move the last named valve away from 'the inwardly facing valve seat, the casing being formed with an open; ing leading from the third bore tothe atmosphere, and with passages establishing communication between t-he third bore and the other two bores, and a plug closing l the end of the third bore and formed with an annular groove in registry with the pas sages, the plug being also formed with a re-y cess establishing Communication between the said opening and said groove, for the purpose specified.

In testimony whereof I hereunto affix my signature inthe presence of two witnesses.

JOSEPH B.'POLO.

-. Witnesses E. E. VVALSETH, J. H. BREKKEN. 

